Absorbent articles with water disintegratability, such as water disintegratable sanitary napkins, panty liners and urine-absorbing pads, have been developed and are marketed. Such absorbent articles are composed of water disintegratable materials, and when flushed through large amounts of water, such as in a flush toilet, they disperse in the water.
Such absorbent articles usually include on the back sheet a pressure-sensitive adhesive section to attach the absorbent article to clothing, such as underwear, and often have a flat pressure-sensitive adhesive section coated on a flat back sheet. Therefore, when the unused absorbent article from which the release sheet has been released is accidentally discarded in a flush toilet, the entire surface of the pressure-sensitive adhesive section sometimes clings to the toilet bowl and is difficult to peel off. In addition, if it is flushed without clinging to the toilet bowl, it can cling to the inner walls of the sewage pipes, causing clogging of pipes.
In order to solve this problem, PTL 1, for example, discloses a water disintegratable absorbent article having, on the back side of a back sheet, pressure-sensitive adhesive sections provided at a plurality of locations at spacings in the longitudinal direction and the transverse direction of the absorbent article, to affix the absorbent article to an exterior attachment surface, wherein the spacing between adjacent pressure-sensitive adhesive sections is longer than the maximum fiber length of the fibers in the back sheet. FIG. 4 of PTL 1 discloses an absorbent article in which a plurality of dot-like pressure-sensitive adhesive sections are configured in a zigzag fashion.
PTL 2 describes an absorbent article that includes an adhesive system comprising a plurality of three-dimensional protruding sections that are deformable essentially in a two-dimensional architecture, and an interconnected network structure of an adhesive surrounding the protruding sections, which prevents inadvertent contact of the three-dimensional protruding sections with the outer walls until it deforms essentially in a two-dimensional architecture. With the absorbent article described in PTL 2, the adhesive surface is protected by the three-dimensional protruding sections, and therefore even if it is accidentally flushed into a flush toilet before wear, there is a low chance of it clinging to the toilet bowl or inner walls of the pipes.